Run, with its extended field of strategy, its quick changes of plan, its fluctuating chances and combinations, and its rapidly shifting incidents and accidents, is a most interesting, and likely to become a typical, “game of war” between volunteer armies. The loyal people in Washington were rejoicing over a victory, steadily reported during the greater part of the day, when suddenly, at about five o'clock, came the startling telegram: “General McDowell's army in full retreat through Centreville.